Recently, the intervention of herbal plants in the fish diet has drawn a lot of interest due
to their unique nutritional value and pharmacological properties. To assess the impact of
dietary incorporation of Egyptian mallow, Malva parviflora leaves powder (MPLP), a
10-week feeding trial was carried out on Nile tilapia (Oreochromis niloticus). The assess
ment encompassed the effects on growth, digestive/absorptive efficiency, biochemical,
and immuno-antioxidant responses. Four treatments containing a total of 200 fish (n = 50
f
ish/treatment; five replicates/treatment; 10 fish/replicate) with an average weight of
37.50 ± 0.22 g (means ± SE) were randomly assigned. The MPLP was added to the basal
diet at 0 (control diet, MPLP0), 5 (MPLP5), 10 (MPLP10), and 15 (MPLP15) g/kg diet
concentrations and served to the fish for 10 weeks. After the trial, the fish were exposed
to pathogenic yeast (Candida albicans) and bacterium (Streptococcus agalactiae) infec
tion. Results displayed that MPLP-incorporated diets significantly (P < 0.05) enhanced the
growth, intestinal digestive enzymes (amylase and lipase), and intestinal morphometrics
(villous length and width and goblet cell count). The increases were in a level-dependent
way, and the MPLP15 diet showed the highest values. Dietary MPLP notably (P < 0.05)
enhanced growth hormone and declined leptin hormone, glucose, and cholesterol levels.
Moreover, the immunological (serum bactericidal activity, myeloperoxidase, and comple
ment 3) and antioxidant (catalase, glutathione peroxidase, and total antioxidant capacity)
biomarkers were augmented in the MPLP-fed groups in a level-dependent way (P < 0.05).
Fifteen days post-infection with C. albicans and S. agalactiae, the survival rates among
the infected fish enhanced as dietary MPLP levels rose; the MPLP15 group had the highest
survival rates (90.91 and 81.82%), respectively. Overall, dietary MPLP intervention can
boost the growth, digestive capacity, disease resistance, and immune-antioxidant status of
Nile tilapia. These positive effects may contribute to a sustainable aquaculture industry |
